as you can see from some of these maps, they shed california as an island and it took a long time for that toy actually get removed from the maps-- old maps, it often took 100 years, maybe 200 years. >> reporter: google and others can react more quickly because of all the input they get. usands of times a day, people all over the world tell google, via the internet, that roads, or signage, or stores or parks have changed, or that a their own neighborhood is poorly represented and that the company needs to update its maps.v erro iestigatethe allec2 , and tries to correct them. the concept of having people on the ground change the map is rsalled crowd sourcing. and it's the principle pioneered by an israeli-based mapping company called waze. that firm, with a small palo alto office, uses g.p.s. to track the location of 27 million drivers who have downloaded its app. waze depends on that crowd to update its maps, determine traffic congestion and direct users to alternate routes. >> so while you're getting a free navigation service, you're also contributing to the community. >> reporter: